在哺乳动物虹膜和视网膜中进行黑色素信号传递
1Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA. txue77@gmail.com
Nature
|November 5, 2011
概括
哺乳动物具有独立于大脑的内在瞳孔光反射 (PLR),涉及黑色素和PLCβ4. 这一途径对于内在光敏的视网膜质细胞中对光反应至关重要.
科学领域:
- 眼科医生 眼科 眼科
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
背景情况:
- 非哺乳动物的脊椎动物表现出内在光敏的虹膜和瞳孔光反射 (PLR).
- 哺乳动物的PLR通常被认为需要眼睛和大脑之间的神经元连接.
研究的目的:
- 研究哺乳动物内在PLR的存在和机制.
- 阐明涉及哺乳动物内在PLR和视网膜光反应的分子组成部分.
主要方法:
- 在小鼠身上研究了内在PLR.
- 使用基因淘汰模型 (Plcb4(-/-)) 来评估PLCβ4.4的作用.
- 检查了表达黑色素的内在光敏感视网膜质细胞 (M1-ipRGCs) 的光反应.
- 研究了切除TRPC6和TRPC7表达的作用.
主要成果:
- PLR的内在组成部分在夜间和夜哺乳动物中广泛存在.
- 在小鼠中,这种内在的PLR依赖于黑色素和PLCβ4.4.
- 缺少plcb4消除了M1-ipRGCs的内在PLR和光反应.
- TRPC6和TRPC7对内在PLR并不重要,但涉及M1-ipRGC光反应.
- 黑色素信号通路在虹膜和视网膜之间分离.
结论:
- 哺乳动物在虹膜中拥有由黑色素和PLCβ4介导的内在PLR.
- PLCβ4依赖性通路对于内在PLR和M1-ipRGC光敏感性都至关重要.
- 在虹膜和视网膜中运行着明显的黑色素信号传递机制.
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